Treatment frees lineages from competition

A proposed mechanism asks whether repeated treatment of middle-aged skin leaves dangerous cell families, descended from one cell, room to grow as lesions clear. Therapy to restore youthful function could alter long-term risk by changing cells that remain. The hypothesis predicts families more likely to survive treatment because cell death is suppressed become enriched after each clearance cycle. With matched cell killing, greater sparing should yield greater enrichment. It offers a test of competition: restoring living neighbours that constrain growth should reduce the surviving family’s expansion between cycles, despite comparable material released by dying cells. Family-specific labels, live imaging and cell counts could distinguish cell death from proliferation.